<template>
  <div class="cicleProgress">
    <svg style="transform: rotate(-90deg);display:block;" :width="width" :height="width" xmlns="http://www.w3.org/2000/svg">
      <circle :r="(width-radius)/2"
        :cy="width/2"
        :cx="width/2"
        :stroke-width="radius"
        :stroke="backgroundColor"
        fill="none"
      />
      <circle ref="$bar"
        :r="(width-radius)/2"
        :cy="width/2"
        :cx="width/2"
        :stroke="barColor"
        :stroke-width="radius"
        :stroke-linecap="isRound ? 'round' : 'square'"
        :stroke-dasharray="(width-radius)*3.14"
        :stroke-dashoffset="isAnimation ? (width-radius) * 3.14 : (width - radius) * 3.14 * (100 - progress) / 100"
        fill="none"
      />
    </svg>
  </div>
</template>

<script>
export default {
  name:'cicleProgress',
  props: {
    width: [Number, String], // 圆的大小
    radius: [Number, String], // 进度条厚度
    progress: [Number, String], // 进度条百分比
    barColor: String, // 进度条颜色
    backgroundColor: String, // 背景颜色
    isAnimation: { // 是否是动画效果
      type: Boolean,
      default: true,
    },
    isRound: { // 是否是圆形画笔
      type: Boolean,
      default: true,
    },
    id: { // 组件的id，多组件共存时使用
      type: [String, Number],
      default: 1,
    },
    duration: { // 整个动画时长
      type: [String, Number],
      default: 1000,
    },
    delay: { // 延迟多久执行
      type: [String, Number],
      default: 200,
    },
    timeFunction: { // 动画缓动函数
      type: String,
      default: 'cubic-bezier(0.99, 0.01, 0.22, 0.94)',
    },
  },
  data() {
    return {
      idStr: `circle_progress_keyframes_${this.id}`
    }
  },
  beforeDestroy() {
    // 清除旧组件的样式标签
    document.getElementById(this.idStr) && document.getElementById(this.idStr).remove()
  },
  mounted() {
    if (this.isAnimation) {
      // 重复定义判断
      if (document.getElementById(this.idStr)) {
        console.warn('vue-circle-progress should not have same id style')
        document.getElementById(this.idStr).remove()
      }
      // 生成动画样式文件
      let style = document.createElement('style')
      style.id = this.idStr
      style.type = 'text/css'
      style.innerHTML = `
      @keyframes circle_progress_keyframes_name_${this.id} {
      from {stroke-dashoffset: ${(this.width - this.radius) * 3.14}px;}
      to {stroke-dashoffset: ${(this.width - this.radius) * 3.14 * (100 - this.progress) / 100}px;}}
      .circle_progress_bar${this.id} {animation: circle_progress_keyframes_name_${this.id} ${this.duration}ms ${this.delay}ms ${this.timeFunction} forwards;}`
      // 添加新样式文件
      document.getElementsByTagName('head')[0].appendChild(style)
      // 往svg元素中添加动画class
      this.$refs.$bar.classList.add(`circle_progress_bar${this.id}`)
    }
  },
}
</script>